Formula: Sc(PO4).2H2O
Hydrated normal phosphate, metavariscite group
Specific gravity: 2.35
Hardness: 3 to 5
Streak: White
Colour: Colourless, light yellow; when impure: cyan-blue, blue-gray, apple-green
Solubility: Decomposed by acids

Hydrothermal environments

Kolbeckite is one of the few scandium-bearing minerals. It is a rare secondary mineral in phosphate deposits and some hydrothermal veins. Associated minerals include crandallite, gypsum, lithiophorite, malhmoodite, variscite, vernadite and wardite (Mindat).


At Putty Beach, Woy Woy Peninsula, Woy Woy, Northumberland county, New South Wales, Australia, kolbeckite is associated with lithiophorite, vernadite and gypsum (HOM).

At the type locality, Sadisdorf, Dippoldiswalde, Sächsische Schweiz-Osterzgebirge, Saxony, Germany, kolbeckite is found in a quartz hübnerite-ferberite vein (Dana), associated with quartz and chlorite (Mindat, HOM).

At the Baia Sprie mine, Baia Sprie, Maramureș, Romania, kolbeckite is associated with miargyrite and diaphorite (HOM).

At the North Wilson pit, Union Carbide Mine, Wilson Springs, Garland county, Arkansas, USA, kolbeckite is associated with malhmoodite (HOM).

At the Little Green Monster Variscite Mine, Clay Canyon, Fairfield, Oquirrh Mountains, Utah county, Utah, USA, kolbeckite is associated with wardite, crandallite and variscite (HOM).

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